PARENTS TO BE: Christina and Matt are reportedly expecting their first baby together [GETTY]

Not only has the singer just got engaged to her boyfriend of three years Matthew Rutler, but it looks like her family is about to get even better.

The 33-year-old is reportedly pregnant with her second child – her first with film producer Matt.

While the couple are yet to confirm that they are expecting, Matt's mum Kathleen Rutler let the cat out of the bag while speaking to Us Weekly.

Christina's in-law said that she had "been sort of told not to say anything", and while commenting on whether the couple would be moving from LA to the East Coast, said: "I don’t know what their plans are. But when you have a baby, you’re not planning on moving anywhere anytime soon!"

HAPPY FAMILIES: Matt and Christina have just got engaged [GETTY]

Former The Voice judge Aguilera is already mum to six-year-old Max, her son from her marriage to Jordan Bratman.

The Dirrty singer married Bratman back in 2005, but their divorce was finalised on Valentine's Day, 2011.

And Christina found herself with another ring on her finger exactly three years later, when Matt proposed on the romantic day two weeks ago.

The blonde babe met Matt, who was working as a set assistant, on the set of Burlesque in 2010, shortly after her break-up from Bratman.

EXCITING TIMES: Matt proposed on Valentine's Day [TWITTER]

Christina revealed the news of her engagement via Twitter, posting a sweet snap reading: "He asked and I said…"

The picture shows the couple holding hands in front of the sea, while Christina displays a hefty sparkler on her ring finger.

The pregnancy comes after former Mouseketeer Christina dieted and exercised her way down to her tiny pre-baby frame.

She has left her post as a coach on the US Voice, and has been replaced by Shakira.